In recent years, airbag devices have become standard equipment for most vehicles. The airbag device is a safety device activated in an emergency event such as a vehicle collision and inflated and deployed by gas pressure to receive and protect an occupant. There are different kinds of airbag devices for various installation locations or uses. For example, a front airbag or frontal impact airbag is provided in the center of the steering at the driver's seat in order to protect the occupant of the front seat against an impact given mainly in the front-back direction, and a passenger airbag is provided at the instrument panel or other locations near a front passenger seat. In addition, a curtain airbag that is inflated and deployed along the side windows is provided at the wall part near the roof in order to protect occupants of the front and back seats against a side collision (or side impact) and a subsequent roll over (turn over), and a side airbag that is inflated and deployed just beside an occupant is provided at a side of each seat.
An airbag disclosed in Japanese Patent Application Publication No. 2003-335203 is mainly for a front passenger seat and configured to restrain an occupant between two bag-shaped parts. More specifically, referring to the above-referenced application, the airbag includes a flat shaped left half airbag 12 and a right half airbag 14, and a space part between these airbags is positioned in front of the seat. The left half airbag 12 and the right half airbag 14 are connected by a tie panel 16 positioned on the vehicle rear side and never apart more than necessary. As a result of the configuration, the airbag disclosed in in the above-referenced document allows an occupant to enter, to a suitable extent, the space part in front and to be received therein.
Today, the airbag devices must cope with irregular collisions or impacts such as a so-called oblique collision that applies an impact on a vehicle obliquely in the front-back direction. In an oblique collision, an occupant enters an airbag cushion (hereinafter referred to as a “cushion”) present in front of the seat in an irregular behavior such as movement in an oblique direction. In the configuration disclosed in the above-mentioned reference, the space part positioned in front of the seat receives the occupant, and therefore the occupant cannot efficiently be restrained in an oblique collision. In order to provide sufficient restraining capability upon an oblique collision, a cushion in a form or structure suitable therefor must be provided, and the cushion must also be kept in an optimal position.
The present invention is in consideration of the problem and it is an object of the present invention to provide an airbag device capable of restraining an occupant in a stable position even upon an oblique collision and lowering an injury value related to the occupant.